1. Which of the following is NOT a function of the cardiovascular system?

A. Transporting oxygen to cells
B. Maintaining blood pressure
C. Carrying waste products to the kidneys for removal
D. Initiating the immune response

Correct answer: D

Rationale: The cardiovascular system is responsible for transporting oxygen to cells (option A), maintaining blood pressure (option B), and carrying waste products to the kidneys for removal (option C). However, initiating the immune response (option D) is not a function of the cardiovascular system. The immune response is primarily carried out by the immune system, which includes organs like the spleen and lymph nodes. While the cardiovascular system does play a role in immune function by transporting immune cells and antibodies, it is not responsible for initiating the immune response. Therefore, option D is the correct answer.

2. Which of the following questions is NOT appropriate for scientific investigation?

A. How can we reduce greenhouse gas emissions?
B. Is there intelligent life beyond Earth?
C. What is the meaning of life?
D. Does free will exist?

Correct answer: C

Rationale: Science deals with observable, measurable phenomena using evidence-based methods. Questions about subjective experiences and abstract concepts like meaning fall outside the realm of scientific inquiry.

3. In the context of cholesterol levels, LDL cholesterol is often referred to as:

A. HDL or "good" cholesterol.
B. LDL or "bad" cholesterol.
C. Total cholesterol, encompassing both LDL and HDL
D. VLDL, a type of triglyceride transported in the bloodstream

Correct answer: B

Rationale: The correct answer is B: LDL or "bad" cholesterol. LDL stands for low-density lipoprotein, which is often referred to as "bad" cholesterol because it can contribute to plaque buildup in the arteries, leading to a higher risk of heart disease. HDL, on the other hand, is known as "good" cholesterol because it helps remove LDL from the bloodstream. Total cholesterol (option C) encompasses both LDL and HDL levels but does not specifically refer to LDL cholesterol. VLDL (option D) is a different type of lipoprotein that transports triglycerides, not cholesterol. Understanding the distinction between LDL and HDL cholesterol is crucial for managing heart health.

4. What is the difference between heat and temperature?

A. They are the same thing.
B. Heat is a form of energy, while temperature measures the average kinetic energy of particles.
C. Heat flows from cold to hot, while temperature flows from hot to cold.
D. Heat is measured in Celsius, while temperature is measured in Joules.

Correct answer: B

Rationale: Heat is a form of energy transfer, while temperature reflects the average kinetic energy of particles within a substance.

5. What do isotopes of the same element have in common?

A. Identical number of protons and neutrons.
B. Identical chemical properties.
C. Identical number of electrons.
D. Identical mass number.

Correct answer: A

Rationale: Identical number of protons and neutrons - Isotopes have the same atomic number but different mass numbers due to varying neutron counts.

6. Which hormone plays a key role in stimulating the release of milk from breast tissue after childbirth?

A. Follicle-stimulating hormone (FSH)
B. Luteinizing hormone (LH)
C. Prolactin
D. Estrogen

Correct answer: C

Rationale: The correct answer is C: Prolactin. Prolactin is the hormone responsible for stimulating the production and release of milk from breast tissue after childbirth. It is produced by the pituitary gland and plays a crucial role in lactation. FSH and LH are reproductive hormones involved in the menstrual cycle and ovulation, not milk production. Estrogen is a sex hormone that plays a role in the development of female reproductive organs. Therefore, the hormone that specifically stimulates milk release from breast tissue after childbirth is prolactin.